The invention concerns a cleaning apparatus for the cleaning of a spin rotor in a rotor spinning machine, with a cleaning head which can be insertably presented to a spin rotor on which at least two scraper elements are placed and the invention also concerns a scraper element corresponding thereto.
U.S. Pat. No. 4,339,914 discloses a cleaning apparatus which is mounted on a service cart which is capable of movement, whereby the apparatus can be presented to a spin rotor for the cleaning of the same. On the cleaning head of the cleaning apparatus, a scraper is placed, which, by means of a pneumatic cylinder can cleaningly enter into the rotor groove of the spin rotor. For the cleaning of the rotor groove, the spin rotor is caused to rotate. In order to achieve a sufficient cleaning effect, the scraper must be subjected to pressure to achieve a correspondingly sufficient force of cleaning contact. On this account, the spin rotor receives an asymmetric loading, which especially contributes to a tilting of the rotor in its bearing, and because of the necessity of rotating the rotor, a one-sided, atypical operational loading of the spin rotor results. As rotor bearing technology advances, and with the development of aero and magnetic bearings, the bearings have become more sensitive in regard to such nontypical loadings.
The DE 26 29 161 shows various embodiments of cleaning apparatuses, these being equipped with different accoutrements including scrapers, brushes and compressed air nozzles. In one embodiment, two oppositely situated scraper elements can penetrate into the rotor groove. In this arrangement, the scraper elements are fastened on one end on leaf springs, while the other end thereof is affixed to a pivoting axle. In order to insert the cleaning head, the leaf springs are pretensioned in the direction of the pivot axle, so that the scrapers can penetrate through an opening in the rotor bowl. After the penetration, the axle is rotated. By centrifugal force, the scrapers withdraw from the leaf springs until the scrapers enter the rotor groove. Because of the spring loading, the contacting force of the scrapers is essentially determined by the centrifugal force. Due to the resilient support, the scraper elements can begin to oscillate inside the rotor groove, so that the cleaning effectiveness cannot be uniform. The adjustment of the contacting force by means of changing the centrifugal force is limited in its possibilities and hence a secure application of the cleaning elements in the rotor groove cannot be assured.